Test Code: 823
CPT Code(s): 84460
Includes: AST
Methodology: Spectrophotometry (SP)
Clinical Significance: Alanine Aminotransferase (ALT) measurements are particularly useful in the diagnosis and management of certain liver diseases, e.g., viral hepatitis and cirrhosis. ALT activity in tissue is generally much lower than aspartate aminotransferase (AST) activity and is found in highest concentrations in the liver. Significant elevations of ALT occur only in diseases of the liver. ALT is often measured in conjunction with AST to determine whether the source of the AST is the liver or the heart. ALT is normally not elevated in cases of myocardial infarction, i.e., a normal ALT, in conjunction with an elevated AST, tends to suggest cardiac disease. However, slight elevations of ALT may occur if an infarct destroys a very large volume of heart muscle.
Alternative Name(s): ALT, SGPT
Supply: #T157 Red/Yellow SST 8mL
Preferred Specimen: Serum
Preferred Volume: 1mL
Transport Container: Serum Separator Tube (SST)
Transport Temperature: Room Temperature
Specimen Stability: Room Temperature: 4 days
Rejection Criteria:
- Hemolysis
- What are hemolyzed specimens?
- Hemolysis occurs when the red cells are damaged during sample collection causing them to rupture. Hemolyzed serum or plasma is pale pink to red rather than the normal clear straw or pale-yellow color.
- What causes a specimen to be hemolyzed?
- Mixing tubes too vigorously
- Placing tubes in the refrigerator without allowing 30 minutes at room temperature for complete clotting
- Exposure to heat or in a refrigerator that is too cold
- Using a needle with too small of a bore necessary for the venipuncture
- Using too large a tube when using a butterfly needle
- Not allowing sufficient time for alcohol to dry on puncture site
- Leaving the tourniquet on for longer than one minute
- How can hemolyzed specimens be prevented?
- For routine collections, use a 20–22-gauge needle
- Do not remove the needle from the vein with the vacuum tube engaged
- Do not collect a specimen in a hematoma
- Do not centrifuge the specimen for a prolonged period of time
- Draw the sample gently and evenly
- What are hemolyzed specimens?
- Specimens exceeding stability
- Specimens other than serum
- Unlabeled or improperly labeled specimens
NOTE: The assay manufacturer, Beckman Coulter, warns that patients treated with Sulfalazine may generate false low results for ALT. Trauma to striated muscle, tissue, rhabdomyolysis, polymyositis, and dermatomyositis may produce increased results. Hemolyzed samples may yield elevated results. Some illegal drugs (cocaine, anabolic steroids, ecstasy) may also produce increased results.
For additional supply or collection device information, please contact DLO's Customer Service at (800) 891-2917, option 2.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the Payor being billed.